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PROCEEDINGS OP THE AMERICAN ACADEMY 



TABLE OF MEASUREMENTS. 



EXPLANATION OF TABLE. 



The foregoing summarj- presents in a tabulated form the results of a series of 

 measurements of, first (column A), tiie distance from the anterior (ventral) edge 

 of the lumen of the central canal to the bottom of tlie anterior fissure (I'l. I. fig. 

 1, a to y), and, secondly (column B), the length of the epithelial cells at the 



